President Donald Trump’s feud with intelligence agencies has drawn headlines, but he is not the first president to ignore intelligence information or seek advice elsewhere.

The spectacle of back and forth jabs on Twitter is new to presidential politics in the United States, as is the president’s early and public criticism of the intelligence agencies. Trump took the unusual step of seeking a political ally from the world of finance to lead a review of the intelligence community, a group of 16 military and civilian agencies in the US government. The review was announced even before the Director of National Intelligence nominee, Dan Coats, was confirmed.

There are four principle reasons why presidents and their advisers may not act, even when the situation seems to call for it. First, advisors may withhold information that they know will not please the president or reinforce his preferred policies. The most infamous example is the Vietnam War, when President Richard Nixon’s advisers withheld assessments of the Vietcong’s strength and wildly overestimated American superiority. Second, the president may receive intelligence information, but not acknowledge it publicly. If President Barack Obama had received information about Syria crossing one of his “red lines” with the use of chemical weapons, he may not have wished to acknowledge the violation if doing so would upset progress on a peace agreement.

Third, presidents may seek plausible deniability. The CIA never told President George W. Bush the locations of its black site prisons, and the president had no reason to want to know the specific details because remaining in the dark provided protection. The logic of the Iran-Contra Affair was also that the president could not be seen to be in the loop.

Fourth, presidents may pursue opacity rather than clarity in cases in which certainty about some event would upset the global strategic balance or harm a president’s foreign policy interests. The novel feature of opacity occurs when presidents take steps to move from relative certainty to relative uncertainty about an event by, for example, expanding the scope of the problem or introducing new information, or establishing a commission to study an issue. We illustrate the pursuit of opacity using the example of the alleged secret Israeli–South African nuclear test in 1979, known as the “flash” over the South Atlantic. Leonard Weiss has also written about the test recently.

What can we, the public and concerned public officials, do about situations where the president doesn’t want intelligence information and would prefer to proceed on a need not to know basis?

First, putting the executive and legislative branches on equal footing with regards to the intelligence community could help. Recent decades have seen the relationship with Congress relegated to second-tier status, and enhanced committee staff and oversight could boost Congress’ role relative to the president’s.

Second, agencies that put dissenting information on the record could help push the information into the policy process over the long term. Prior to the Iraq war, the State Department’s Bureau of I&R and the International Atomic Energy Agency poured cold water on the idea that Iraq had an active WMD program. The president didn’t listen, but putting dissenting voices on record ensured that the Bush administration and Congress’ decision to go to war wasn’t seen as inevitable, and it constrained future administration pronouncements.

These strategies will not ensure that the president will use intelligence findings, but they do make it more likely that the intelligence community’s work will see the light of day.